Filter for a smoking article

ABSTRACT

A filter for a smoking article has a first filter section comprising a filter material and a smoke modifying additive disposed in an axial region thereof and a second filter section connected to the first filter section and having at least one channel located in an axial region thereof for directing smoke, in use, through the axial region of the first filter section. The smoke modifying additive can comprise a flavourant such as menthol and the second filter section can comprise a tubular section of fibrous filter material. An adsorbent filter section can also be provided.

TECHNICAL FIELD

The invention relates to a filter for a smoking article and to a smokingarticle including a filter.

BACKGROUND

Known smoking article filters, such as cigarette filters, generallycomprise a continuous tow of filamentary cellulose acetate. Thecellulose acetate is gathered together to form a rod which is cut toform individual filter sections. The smoking article filter may be madeof one segment of filter rod, or may be made from multiple segments,with or without a cavity or spaces between them.

SUMMARY

According to embodiments of the invention, there is provided a filterfor a smoking article comprising a first filter section comprisingfilter material and a smoke modifying additive disposed in an axialregion thereof and a second filter section connected to said firstfilter section, the second filter section comprising filter material andat least one channel located in an axial region thereof for directingsmoke, in use, through the axial region of the first filter section inwhich the smoke modifying additive is disposed. The first and secondfilter sections can be discrete filter sections and/or the smokemodifying additive can be disposed only in said axial region of thefilter material of the first filter section or in a greaterconcentration in said axial region than in non-axial regions of thefilter material of the first filter section.

The at least one channel can have a lower resistance to smoke passingthrough it than other regions of the filter material of the first filtersection. The channel can be a hollow passageway through the secondfilter section.

The second filter section can be connected to said first filter sectionso as to make the second filter section immediately either downstream orupstream of said first filter section when incorporated into a smokingarticle.

The axial region of said filter material of said first and/or secondfilter sections can have a radius of from 1 mm to 4 mm and/or can becentred on the axis of the smoking article.

The first filter section can comprise continuous filter material havingthe smoke modifying additive disposed in the axial region thereof. Thesecond filter section can comprise a tubular filter section. The tubularfilter section can be formed from a fibrous filter material.

The smoke modifying additive can be disposed in a greater concentrationin said axial region than in non-axial regions of the filter material ofthe first filter section.

The smoke modifying additive can be disposed only in said axial regionof the filter material of the first filter section.

The second filter section can be configured, in use, to direct a greaterportion of smoke through the axial region of the first filter sectionthan through non-axial regions of the first filter section.

The smoke modifying additive can comprise an encapsulated additive. Thesmoke modifying additive can be contained within a capsule which islocated within the first filter section at a position other than alongitudinally central position within the first filter section.

The capsule can be located within the first filter section at a positionfrom 1 mm to 10 mm from a longitudinally central position within thefirst filter section.

The smoke modifying additive can be disposed on a carrier material. Thecarrier material can comprise a thread.

The filter can further comprise a third filter section connected to saidfirst filter section so as to make it upstream of said first filtersection when incorporated into a smoking article. The third filtersection can be a discrete filter section. The third filter section cancomprise fibrous filter material and a granular adsorbent material. Thegranular adsorbent material can be disposed in a circumferential regionof the third filter section, dispersed within the filter material of thethird filter section, or comprises some granular adsorbent materialdisposed in a circumferential region of the third filter section andsome granular adsorbent material dispersed within the third filtersection.

According to embodiments of the invention, there is also provided asmoking article comprising a filter as defined above.

The second filter section can be arranged immediately downstream of saidfirst filter section and at the mouth-end of the smoking article.

According to embodiments of the invention, there is further provided asmoking article comprising a first section comprising an aerosolgenerating material and an aerosol modifying additive disposed in anaxial region thereof, and a second section comprising a filter having atleast one channel located in an axial region thereof for directing theaerosol generated by the aerosol generating material, in use, throughthe axial region of the first section.

The second section can comprise a tubular filter section. The tubularfilter section can be formed from a fibrous filter material.

The aerosol modifying additive can be disposed in a greaterconcentration in said axial region than in non-axial regions of theaerosol generating material of the first section.

The second section, in use, can direct a greater portion of smokethrough the axial region of the first section than through non-axialregions of the first section.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of exampleonly, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic illustration of a smoking article having a filterwith a tubular downstream filter section and an upstream filter sectionincluding an encapsulated additive in the form of a frangible capsule;

FIG. 2 is a schematic illustration of a smoking article having a filterwith a tubular filter section and a filter section including a threadcarrying an additive;

FIG. 3 is a schematic illustration of a smoking article having a filterwith a tubular filter section and a filter section including anencapsulated additive in the form of a plurality of frangible capsules;

FIG. 4 is a schematic illustration of a smoking article having a filtersimilar to that described with reference to FIG. 1 but also including afurther filter section having an adsorbent dispersed in filter material;

FIG. 5 is a schematic illustration of a smoking article having a filtersimilar to that described with reference to FIG. 2 but also comprising afurther filter section comprising an adsorbent dispersed in filtermaterial and disposed in a circumferential region of the filtermaterial;

FIG. 6 is a schematic illustration of a smoking article with an aerosolgenerating section and a tubular filter section, the aerosol generatingsection having an encapsulated additive in the form of a plurality ofmicrocapsules dispersed within an axial region thereof; and

FIG. 7 is a schematic illustration of a smoking article having a filterwith a tubular upstream filter section and a downstream filter sectionincluding an encapsulated additive in the form of a frangible capsule.

DETAILED DESCRIPTION

As used herein, the term “smoking article” includes smokeable productssuch as cigarettes, cigars and cigarillos whether based on tobacco,tobacco derivatives, expanded tobacco, reconstituted tobacco or tobaccosubstitutes and also heat-not-burn products and other nicotine deliverydevices capable of generating an aerosol for delivery to a consumer.Such smoking articles may be provided with a filter for the gaseous flowdrawn by the smoker.

Smoking articles such as cigarettes and their formats are often namedaccording to the cigarette length: “regular” (typically in the range68-75 mm, e.g. from about 68 mm to about 72 mm), “short” or “mini” (68mm or less), “king-size” (typically in the range 75-91 mm, e.g. fromabout 79 mm to about 88 mm), “long” or “super-king” (typically in therange 91-105 mm, e.g. from about 94 mm to about 101 mm) and “ultra-long”(typically in the range from about 110 mm to about 121 mm).

They are also named according to the cigarette circumference: “regular”(about 23-25 mm), “wide” (greater than 25 mm), “slim” (about 22-23 mm),“demi-slim” (about 19-22 mm), “super-slim” (about 16-19 mm), and“micro-slim” (less than about 16 mm). Accordingly, a cigarette in aking-size, super-slim format will, for example, have a length of about83 mm and a circumference of about 17 mm. Cigarettes in the regular,king-size format are preferred by many customers, namely with acircumference of from 23 to 25 mm and an overall length of from 75 to 91mm.

Each format may be produced with filters of different lengths, smallerfilters being generally used in formats of smaller lengths andcircumferences. Typically the filter length will be from 15 mm,associated with short, regular formats, to 30 mm, associated withultra-long super-slim formats. The tipping paper will have a greaterlength than the filter, for example from 3 to 10 mm longer.

Smoking articles and filters described hereinafter can be manufacturedin any of the above formats. The smoking article can, for instance, befrom 70 to 100 mm in length and from 14 to 25 mm in circumference.

The terms ‘upstream’ and ‘downstream’ used herein are relative termsdefined in relation to the direction of mainstream smoke (or otheraerosol) drawn though a smoking article in use.

FIG. 1 is a schematic illustration of a smoking article 1 which isgenerally cylindrical in shape and is in the regular, king size format,namely having a length in the range 75-91 mm and a circumference in therange 23 to 25 mm. The smoking article 1 includes a tobacco rod 2wrapped in a wrapping material 3, in this example cigarette paper,connected longitudinally to a filter 4 by tipping material 5 overlayingthe filter 4 and partially overlaying the wrapping material 3 so as toconnect the filter 4 to the tobacco rod 2. The filter 4 comprises afirst section 6 at the tobacco rod end of the filter 4 comprisingabsorbent material 7 having a capsule 8 disposed therein in an axialregion of the filter material of the first section 6. The axial regionis a region, in the present example, centred on the axis ‘a’ of thesmoking article 1, having a radius of about 3 mm. In alternativeembodiments, the radius of the axial region can be anywhere from 1 mm to4 mm, or from 1 mm to 3 mm, or about 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm or3.5 mm.

The capsule 8, or other additive material, can be disposed only in theaxial region of the filter material of the first filter section 6, orcan be disposed in greater concentration in the axial region than innon-axial regions of the filter material of the first filter section 6.The first section is wrapped in a first plug wrap 9.

The filter 4 further comprises a second section 10 at the mouth-end ofthe filter 4 comprising fibrous filter material n formed into a tubularshape and having a channel 12 extending through the centre of the filtermaterial 11. The empty or hollow channel 12 extending through the centreof the filter material 11 can be from 1 mm to 6 mm in diameter, forinstance from 2 mm to 5 mm in diameter. The channel 12 extending throughthe centre of the filter material 11 is, in the present example, anempty, hollow passageway. The channel, in some embodiments, extendsthrough an axial region of the filter material of the second filtersection 10. The axial region of the second filter section 10 is aregion, in the present example, centred on the axis ‘a’ of the smokingarticle 1, having a radius of about 2.5 mm. In alternative embodiments,the radius of the axial region can be anywhere from 1 mm to 4 mm, orfrom 1 mm to 3 mm, or about 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm or 3.5 mm.In the present example, the tubular filter section is formed fromcellulose acetate tow and is wrapped in a second plug wrap 13. The wallthickness of the tubular filter is about 1.5 mm. In alternativeembodiments, the wall thickness can be anywhere from 1 mm to 4 mm, orfrom 1 mm to 3 mm, or about 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm or 3.5 mm.However, the specific dimensions may be selected based on the density offilter material forming the tube and the level of plasticiser applied tothe material, to result in a tube having the desired rigidity, porosityor other characteristics. The tubular filter section 10 can bemanufactured using existing processes and machinery.

The first segment 6 is a cellulose acetate segment formed usingcontinuous cellulose acetate fibres and a plasticiser. The capsule 8 isspherical and has a diameter of 3.5 mm, although other shapes and sizesof capsule can be used, and contains a fluid additive which modifiesproperties of mainstream smoke passing through the smoking article 1.The capsule 8 can be manufactured and inserted into the first filtersection 6 using existing processes and machinery. In the presentexample, the capsule 8 contains menthol flavourant, although otherfluids or granular additives could be contained within the capsule 8.The capsule can be ruptured by a consumer to release the fluid additiveinto the absorbent filter material 11.

The axis of the smoking article 1, about which the tobacco rod 2 andfirst and second filter sections 6, 10 are aligned, is indicated as ‘a’in FIG. 1.

In the present example, the capsule 8 is located in an ‘axial region’ ofthe first filter section 6, as defined above. The capsule 8 can belocated such that the centre of the capsule is closer to the axis ‘a’ ofthe smoking article 1 than to the outer periphery of the smoking article1. In the present example, the capsule 8 is located with its centresubstantially along the axis ‘a’. In the present example, the capsule 8is offset from the longitudinal centre of the first filter section 6.The capsule 8 can, for instance, be located within the first filtersection 6 at a position from 1 mm to 10 mm from a longitudinally centralposition within the first filter section 6. The capsule 8 is locatedwithin a portion of the first filter section 6 closer to the downstreamend of the first filter section 6. The capsule 8 is therefore closer tothe second filter section 10 than to the tobacco rod 2. In particular,the distance ‘d’ between the centre of the capsule 8 and the downstreamend of the first filter section 6 is less than half of the totallongitudinal length of the first filter section 6. In some embodiments,the distance ‘d’ is less than 40%, less than 30% or less than 25% of thetotal longitudinal length of the first filter section 6. In the presentexample, the distance ‘d’ is approximately 30% of the total longitudinallength of the first filter section 6. In alternative embodiments, thecapsule 8 can be located longitudinally centrally within the firstfilter section 6 or closer to the upstream end of the first filtersection 6 than to the downstream end.

The smoking article 1 is, in the present example, provided withventilation holes (not shown) through the tipping material 5 and firstplug wrap 9, providing ventilation into the first filter section 6. Ifformed by online laser perforation, the ventilation holes are preferablylocated in a longitudinal position other than that in which the capsule8 is located, to avoid damaging the capsule 8 during manufacture. Forinstance, in a smoking article with a first upstream filter section 6 oflength 20 mm and a second downstream filter section 10 of length 7 mm,ventilation may be provided at 20 mm from the mouth end, while thecapsule 8 is longitudinally centrally located within the first filtersection and, at 3.5 mm diameter, therefore extends from 15.25 mm to18.75 mm from the mouth end.

In use, the tobacco rod 2 of the smoking article 1 is lit by a consumerin the conventional manner and tobacco smoke is drawn from burning coalof the tobacco rod 2 through the filter 4. The channel 12 in the secondfilter section 10 has a lower resistance to mainstream smoke passingthrough the filter 4 than the surrounding tubular filter material 11,and therefore a greater proportion of mainstream smoke is directedthrough the channel 12. This, in turn, results in a greater flow ofmainstream smoke in the axial region around the axis ‘a’ of the firstfilter section 6, in which the capsule 8 is located. When the consumerbreaks the capsule 8 either prior to or in the course of smoking thesmoking article 1, the smoke modifying additive contained therein, inthe present case menthol, is released in greater concentration into theaxial region of the first filter section 6 through which an increasedflow of mainstream smoke is directed, as a result of the second filtersection 10. Accordingly, the increased flow of mainstream smoke enhancesthe delivery of the smoke modifying additive to the consumer and thesmoking article 1 can therefore exhibit improved delivery of a smokemodifying additive to a consumer compared to conventional smokingarticles.

Since the capsule 8 is located within a portion of the first filtersection 6 closer to the second filter section 10 than to the tobacco rod2, the effect of the increased flow of mainstream smoke on the contentsof the capsule 8, once released, is further enhanced. The use of thetubular second section 10 at the mouth end of the smoking article 1enables the capsule 8 to be located closer to the mouth-end of thesmoking article 1 than would be possible if the first section 6containing the capsule 8 were at the mouth end of the smoking article 1.This is because the tube separates the first section 6 from theconsumer's mouth, preventing the content from the capsule 8 fromcontacting the consumer's mouth.

FIG. 2 is a schematic illustration of a smoking article 21 having afilter according to a further embodiment of the invention. The featuresof the smoking article 21 are the same as those of the smoking article 1described with reference to FIG. 1, unless otherwise stated below. Thesmoking article 21 includes a tobacco rod 22 wrapped in a wrappingmaterial 23, in this example cigarette paper, connected longitudinallyto a filter 24 by tipping material 25 overlaying the filter 24 andpartially overlaying the wrapping material 23. The filter 24 comprises afirst section 26 at the tobacco rod end of the filter 24 comprisingabsorbent material 27. In the present case, rather than having a capsule8 disposed in the first filter section, the absorbent material 27 has anadditive carrying thread 28 disposed therein in an axial region (notshown) of the first section 26, wherein the axial region of the firstfilter section 26 is as defined in relation to the first filter section6 of the smoking article 1 described above. The thread can, forinstance, be formed from cotton or cellulose acetate fibres and beloaded with between 0.1 and 10 mg of flavourant, such as mentholflavourant. Loading levels of between 0.2 to 2 mg, or between 0.2 and 1mg of flavourant have been found to be effective. The first section 26is wrapped in a first plug wrap 29. The thread 28 carries an additivecapable of modifying mainstream smoke passing through the filter 24, inthe present case menthol flavourant.

The filter 24 further comprises a second section 30 at the mouth-end ofthe filter 24 comprising fibrous filter material 31 formed into atubular shape and having a channel 32 extending through the centre ofthe filter material 31, or through an axial region thereof, similar tothe second section 10 of the filter 4 of FIG. 1 described above. In thepresent example, the tubular filter section is formed from celluloseacetate tow and is wrapped in a second plug wrap 33.

The first segment 26 is a cellulose acetate segment formed usingcontinuous cellulose acetate fibres and a plasticiser. The thread 28 canbe inserted into the filter material during formation of the filtersection 26 using existing processes and machinery.

In use, the smoking article 21 illustrated in FIG. 2 operates in asimilar way to the smoking article 1 illustrated in FIG. 1. However,rather than breaking a capsule 8 to release a smoke modifying additive,the consumer can simply smoke the smoking article 21 in the usualmanner. When doing so, a greater flow of mainstream smoke is directed,as a result of the second filter section 30, through the axial region ofthe first filter section 26 in which the thread 28 carrying the smokemodifying additive is located. Accordingly, when the smoking article issmoked, the increased flow of mainstream smoke enhances the delivery ofthe smoke modifying additive to the consumer and the smoking article 1can therefore exhibit improved delivery of a smoke modifying additive toa consumer than convention smoking articles.

FIG. 3 is a schematic illustration of a smoking article 41 having afilter according to a further embodiment of the invention. The featuresof the smoking article 41 are the same as those of the smoking article 1described with reference to FIG. 1, unless otherwise stated below. Thesmoking article 41 includes a tobacco rod 42 wrapped in a wrappingmaterial 43, in this example cigarette paper, connected longitudinallyto a filter 44 by tipping material 45 overlaying the filter 44 andpartially overlaying the wrapping material 43. The filter 44 comprises afirst section 46 at the tobacco rod end of the filter 44 comprisingabsorbent material 47. In the present case, rather than having a capsule8 disposed in the first filter section, the absorbent material 47 has aplurality of microcapsules disposed therein in an axial region thereof,the axial region being as defined in relation to the first filtersection 6 of the smoking article 1 described above. The first section 46is wrapped in a first plug wrap 49.

The filter 44 further comprises a second section 50 at the mouth-end ofthe filter 44 comprising fibrous filter material 51 formed into atubular shape and having a channel 52 extending through the centre ofthe filter material 51 or through the axial region thereof, as describedabove with reference to the channel 12 of FIG. 1. In the presentexample, the tubular filter section is formed from cellulose acetate towand is wrapped in a second plug wrap 53.

In use, the smoking article 41 illustrated in FIG. 3 operates in asimilar way to the smoking article 1 illustrated in FIG. 1. However,rather than breaking a single capsule 8 to release a smoke modifyingadditive, the consumer breaks the plurality of microcapsules 48 prior toor in the course of smoking the smoking article 41. When doing so, agreater flow of mainstream smoke is directed, as a result of the secondfilter section 50, through the axial region of the first filter section46 in which the smoke modifying additive released from the microcapsulesis located. Accordingly, when the smoking article is smoked, theincreased flow of mainstream smoke enhances the delivery of the smokemodifying additive to the consumer and the smoking article 41 cantherefore exhibit improved delivery of a smoke modifying additive to aconsumer than convention smoking articles.

FIG. 4 is a schematic illustration of a smoking article 61 having afilter according to a further embodiment of the invention. The featuresof the smoking article 61 are the same as those of the smoking article 1described with reference to FIG. 1, unless otherwise stated below. Thesmoking article 61 includes a tobacco rod 62 wrapped in a wrappingmaterial 63, in this example cigarette paper, connected longitudinallyto a filter 64 by tipping material 65 overlaying the filter 64 andpartially overlaying the wrapping material 63. The filter 64 comprisesthree filter sections, including a first central section 66 comprisingabsorbent material 67 and a capsule 68 disposed in an axial regionthereof, the axial region being as defined in relation to the firstfilter section 6 of the smoking article 1 described above. The firstsection 66 is wrapped in a first plug wrap 69.

A second filter section 70 is disposed at the mouth-end of thethree-part filter 64 and comprises fibrous filter material 71 formedinto a tubular shape and having a channel 72 extending through thecentre of the filter material 71 or through the axial region thereof, asdescribed above with reference to the channel 12 of FIG. 1. In thepresent example, the tubular filter section is formed from celluloseacetate tow and is wrapped in a second plug wrap 73.

A third filter section 74 is disposed at the tobacco-end of thethree-part filter 64 and comprises granules of adsorbent material 75, inthe present case activated carbon granules, dispersed within a fibrousfilter material 76. In the present example, the adsorbent material 75 isformed from cellulose acetate tow and is wrapped in a third plug wrap77. In the present example, 40 mg of activated carbon granules are used,although other amounts, such as between 10 mg and 80 mg or between 10 mgand 50 mg can be used.

In the present example, the capsule 68 is located within a portion ofthe first filter section 66 closer to the downstream end of the firstfilter section 66, or to the second filter section 70, than to theupstream end of the first filter section, or to the tobacco rod 62. Inparticular, the distance ‘d’ between the centre of the capsule 68 andthe downstream end of the first filter section 66 is approximately 30%of the total longitudinal length of the first filter section 66. Inalternative embodiments, the capsule 68 can be located longitudinallycentrally within the first filter section 66 or closer to the upstreamend of the first filter section 66 than to the downstream end.

The first filter section 66 has a length of 10 mm in the presentexample, the second filter section 70 a length of 7 mm and the thirdfilter section 74 a length of 10 mm, although other section lengths canbe used. Ventilation is provided into the third filter section at aposition 22 mm from the mouth end of the smoking article 61.

In use, the smoking article 61 illustrated in FIG. 4 operates in asimilar way to the smoking article 1 illustrated in FIG. 1, with theadditional third filter section 74 providing additional selective smokefiltration upstream of the first filter section 66 and therefore withoutinfluencing the delivery of smoke modifying additive to the consumer.

FIG. 5 is a schematic illustration of a smoking article 81 having afilter according to a further embodiment of the invention. The featuresof the smoking article 81 are the same as those of the smoking article61 described with reference to FIG. 4, unless otherwise stated below.The smoking article 81 includes a tobacco rod 82 wrapped in a wrappingmaterial 83, in this example cigarette paper, connected longitudinallyto a filter 84 by tipping material 85 overlaying the filter 84 andpartially overlaying the wrapping material 83. The filter 84 comprisesthree filter sections, including a first central section 86 comprisingabsorbent material 87 and, rather than a capsule 68, a thread 88disposed therein, in an axial region thereof, the axial region being asdefined in relation to the first filter section 6 of the smoking article1 described above. The first section 86 is wrapped in a first plug wrap89.

A second filter section 90 is disposed at the mouth-end of thethree-part filter 84 and comprises fibrous filter material 91 formedinto a tubular shape and having a channel 92 extending through thecentre of the filter material 91 or through the axial region thereof, asdescribed above with reference to the channel 12 of FIG. 1. In thepresent example, the tubular filter section is formed from celluloseacetate tow and is wrapped in a second plug wrap 93.

A third filter section 94 is disposed at the tobacco-end of thethree-part filter 84 and comprises granules of adsorbent material 95, inthe present case activated carbon granules, dispersed within a fibrousfilter material 96. The third filter section 94 also comprises granulesof adsorbent material 97, in the present case activated carbon granules,dispersed in a circumferential region thereof. However, in alternativeexamples these may be omitted. In the present example, the fibrousfilter material 96 is formed from cellulose acetate tow and the thirdfilter section 94 is wrapped in a third plug wrap 98. The granules ofadsorbent material 97 dispersed in a circumferential region of the thirdfilter section 94 are applied to an inner surface of the plug wrap 98 ina pattern of longitudinally extending strips, four of which are evenlyradially spaced around the third filter section 94. Adhering strips ofgranular adsorbent material 97 to plug wrap in a symmetrical patternabout a filter section can help to prevent the filter section becomingmisshapen as a result of the adhesive used, while maximising the amountof granular material 97 present in the filter section.

The first filter section 86 has a length of 10 mm in the presentexample, the second filter section 90 a length of 7 mm and the thirdfilter section 94 a length of 10 mm, although other section lengths canbe used. Ventilation is, for instance, provided into the first and thirdfilter sections at respective positions of 13 mm and 20 mm from themouth end of the smoking article 81.

In use, the smoking article 81 illustrated in FIG. 5 operates in asimilar way to the smoking article 21 illustrated in FIG. 2, with theadditional third filter section 94 providing additional selective smokefiltration upstream of the first filter section 86 and therefore withoutinfluencing the delivery of smoke modifying additive to the consumer.

FIG. 6 is a schematic illustration of a smoking article 101 according toa further embodiment of the invention. The smoking article 101 isgenerally cylindrical in shape and is in the regular, king size format,namely having a length in the range 75-91 mm and a circumference in therange 23 to 25 mm. The smoking article 101 includes a tobacco rod 102wrapped in a wrapping material 103, in this example cigarette paper,connected longitudinally to a filter 104 by tipping material 105overlaying the filter 104 and partially overlaying the wrapping material103. The filter 104 comprises a first section 106 at the tobacco rod endof the filter 104 comprising absorbent material 107 and wrapped in afirst plug wrap 108.

The filter 4 further comprises a second section 109 at the mouth-end ofthe filter 104 comprising fibrous filter material 110 formed into atubular shape and having a channel 111 extending through the centre ofthe filter material 110 or through the axial region thereof, asdescribed above with reference to the channel 12 of FIG. 1. In thepresent example, the tubular filter section is formed from celluloseacetate tow and is wrapped in a second plug wrap 112.

The tobacco rod 102 includes a plurality of microcapsules 113 disposedin an axial region thereof at the filter end of the tobacco rod 102, theaxial region being similar in location and size to that defined inrelation to the first filter section 6 of the smoking article 1described above, except that it is located within the tobacco rod 102.

The axis of the smoking article 1, along which the tobacco rod 2 andfirst and second filter sections 46, 50 are disposed, is indicated as‘a’ in FIG. 1.

In use, the smoking article 101 illustrated in FIG. 6 operates in asimilar way to the smoking article 41 illustrated in FIG. 3. However,rather than breaking the plurality of microcapsules 48 in a filtersection prior to or in the course of smoking the smoking article 41, theconsumer breaks the plurality of microcapsules 113 located in thetobacco rod 102. When doing so, a greater flow of mainstream smoke isdirected, as a result of the second filter section 109, through theaxial region of the filter end of the tobacco rod 2 in which the smokemodifying additive released from the microcapsules is located. Theincreased flow of mainstream smoke enhances the delivery of the smokemodifying additive to the consumer and the smoking article 101 cantherefore exhibit improved delivery of a smoke modifying additive to aconsumer than convention smoking articles.

FIG. 7 is a schematic illustration of a smoking article 121 having afilter according to a further embodiment of the invention. The featuresof the smoking article 121 are the same as those of the smoking article1 described with reference to FIG. 1, unless otherwise stated below. Thesmoking article 121 includes a tobacco rod 122 wrapped in a wrappingmaterial 123, in this example cigarette paper, connected longitudinallyto a filter 124 by tipping material 125 overlaying the filter 124 andpartially overlaying the wrapping material 123. The filter 124 comprisesa first section 126 at the mouth end of the filter 124, rather than atthe tobacco end of the filter, comprising absorbent material 127 and acapsule 128 disposed in an axial region thereof, the axial region beingas defined in relation to the first filter section 6 of the smokingarticle 1 described above.

The first section 126 is wrapped in a first plug wrap 129. The capsule128 contains an additive capable of modifying mainstream smoke passingthrough the filter 124, in the present case menthol flavourant.

The filter 124 further comprises a second section 130 at the tobacco rodend of the filter 124 rather than at the mouth end of the filter 124comprising fibrous filter material 131 formed into a tubular shape andhaving a channel 132 extending through the centre of the filter material131, or through an axial region thereof, similar to the second section10 of the filter 4 of FIG. 1. In the present example, the tubular filtersection is formed from cellulose acetate tow and is wrapped in a secondplug wrap 133.

The first segment 126 is a cellulose acetate segment formed usingcontinuous cellulose acetate fibres and a plasticiser. The capsule 128can be inserted into the filter material during formation of the filtersection 126 using existing processes and machinery. In the presentexample, the capsule 128 is located within a portion of the first filtersection 126 closer to the upstream end of the first filter section 126,or to the second filter section 130, than to the downstream end of thefirst filter section 126, or to the mouth end of the smoking article121. In particular, the distance ‘d’ between the centre of the capsule128 and the upstream end of the first filter section 126 isapproximately 30% of the total longitudinal length of the first filtersection 126. In alternative embodiments, the capsule 128 can be locatedlongitudinally centrally within the first filter section 126 or closerto the downstream end of the first filter section 126 than to theupstream end.

Although not illustrated, the embodiment of FIG. 7 may also comprise athird filter section upstream of the second filter section 130corresponding to either of the third filter sections 74, 94 describedwith reference to FIGS. 4 and 5.

In use, the smoking article 121 illustrated in FIG. 7 operates in asimilar way to the smoking article 1 illustrated in FIG. 1. When thecapsule 128 is ruptured to release a smoke modifying additive, a greaterflow of mainstream smoke is directed, as a result of the second filtersection 130, through the axial region of the first filter section 126 inwhich the contents of the capsule 128 have been released. Accordingly,when the smoking article is smoked, the increased flow of mainstreamsmoke enhances the delivery of the smoke modifying additive to theconsumer and the smoking article 121 can therefore exhibit improveddelivery of a smoke modifying additive to a consumer than conventionsmoking articles.

Specific embodiments of the invention have been described, although theinvention is not limited to such embodiments. For instance, although thesecond filter section has been described above as a tubular portion offibrous filter material, this may take other forms, such as filtermaterial sections with lower density regions extending through an axialregion thereof. Also, the tubular section or other section havingreduced density in an axial region has been described as being at themouth-end of the filter in some embodiments above, but in any of theembodiments can alternatively be used as a central or upstream end ofmultipart filters, for instance upstream of the section in which thesmoke modifying additive is located, while still benefiting from theeffect of the invention. In particular, the presence of such a filtersection can encourage mainstream smoke to be directed to an axial regionof a smoking article both upstream and downstream of the region, due tothe lower resistance to draw coinciding with the axial region.

The first, second and (where present) third filter sections describedabove are discrete segments. Although the first, second and (wherepresent) third filter sections described above are connected togetherusing tipping material, they are individually separate and distinctfollowing their formation and prior to being connected together. Thetipping material also connects the filter sections to the respectivetobacco rod of each embodiment. In alternative examples of each of thedescribed embodiments, a further plug wrap can be used to connect thefirst, second and (where present) third discrete filter sections beforethey are connected to the tobacco rods using the tipping material.

In order to address various issues and advance the art, the entirety ofthis disclosure shows by way of illustration various embodiments inwhich the claimed invention(s) may be practiced and provide for superiordelivery of a smoke modifying additives. The advantages and features ofthe disclosure are of a representative sample of embodiments only, andare not exhaustive and/or exclusive. They are presented only to assistin understanding and teach the claimed features. It is to be understoodthat advantages, embodiments, examples, functions, features, structures,and/or other aspects of the disclosure are not to be consideredlimitations on the disclosure as defined by the claims or limitations onequivalents to the claims, and that other embodiments may be utilisedand modifications may be made without departing from the scope and/orspirit of the disclosure. Various embodiments may suitably comprise,consist of, or consist essentially of, various combinations of thedisclosed elements, components, features, parts, steps, means, etc. Inaddition, the disclosure includes other inventions not presentlyclaimed, but which may be claimed in future.

1. A filter for a smoking article comprising: a first discrete filtersection comprising filter material and a smoke modifying additivedisposed in an axial region thereof; and a second discrete filtersection connected to said first filter section, the second filtersection comprising filter material and at least one channel located inan axial region of the filter material, for directing smoke, in use,through the axial region of the first filter section in which the smokemodifying additive is disposed, wherein the smoke modifying additive isdisposed only in said axial region of the filter material of the firstfilter section or in a greater concentration in said axial region thanin non-axial regions of the filter material of the first filter section.2. A filter according to claim 1, wherein the at least one channel has alower resistance to smoke passing through it than other regions of thefilter material of the first filter section.
 3. A filter according toclaim 1 or 2, wherein said channel is a hollow passageway through thesecond filter section.
 4. A filter according to any preceding claim,wherein the second filter section is connected to said first filtersection so as to make the second filter section immediately eitherdownstream or upstream of said first filter section when incorporatedinto a smoking article.
 5. A filter according to any preceding claim,wherein said axial region of said filter material of said first and/orsecond filter sections has a radius of from 1 mm to 4 mm and is centredon the axis of the smoking article.
 6. A filter according to anypreceding claim, wherein the first filter section comprises continuousfilter material having the smoke modifying additive disposed in theaxial region thereof.
 7. A filter according to any preceding claim,wherein the second filter section comprises a tubular filter section. 8.A filter according to claim 7, wherein the tubular filter section isformed from a fibrous filter material.
 9. A filter according to any oneof the preceding claims, wherein the second filter section isconfigured, in use, to direct a greater portion of smoke through theaxial region of the first filter section than through non-axial regionsof the first filter section.
 10. A filter according to any one of thepreceding claims, wherein the smoke modifying additive comprises anencapsulated additive.
 11. A filter according to claim 10, wherein thesmoke modifying additive is contained within a capsule which is locatedwithin the first filter section at a position other than alongitudinally central position within the first filter section.
 12. Afilter according to claim ii, wherein the capsule is located within thefirst filter section at a position from 1 mm to 10 mm from alongitudinally central position within the first filter section.
 13. Afilter according to any one of claims 1 to 9, wherein the smokemodifying additive is disposed on a carrier material.
 14. A filteraccording to claim 13, wherein the carrier material comprises a thread.15. A filter according to any preceding claim, further comprising athird discrete filter section connected to said first filter section soas to make it upstream of said first filter section when incorporatedinto a smoking article.
 16. A filter according to claim 15, wherein thethird filter section comprises fibrous filter material and a granularadsorbent material.
 17. A filter according to claim 13, wherein thegranular adsorbent material is disposed in a circumferential region ofthe third filter section, dispersed within the filter material of thethird filter section, or comprises some granular adsorbent materialdisposed in a circumferential region of the third filter section andsome granular adsorbent material dispersed within the third filtersection.
 18. A smoking article comprising a filter according to any oneof the preceding claims.
 19. A smoking article according to claim 18,wherein the second filter section is arranged immediately downstream ofsaid first filter section and at the mouth-end of the smoking article.20. A smoking article comprising: a first section comprising an aerosolgenerating material and an aerosol modifying additive disposed in anaxial region thereof; and a second section comprising a filter having atleast one channel located in an axial region thereof for directing theaerosol generated by the aerosol generating material, in use, throughthe axial region of the first section.
 21. A smoking article accordingto claim 20, wherein the second section comprises a tubular filtersection.
 22. A smoking article according to claim 21, wherein thetubular filter section is formed from a fibrous filter material.
 23. Asmoking article according to any one of claims 20 to 22, wherein theaerosol modifying additive is disposed in a greater concentration insaid axial region than in non-axial regions of the aerosol generatingmaterial of the first section.
 24. A smoking article according to anyone of claims 20 to 23, wherein the second section, in use, directs agreater portion of smoke through the axial region of the first sectionthan through non-axial regions of the first section.